Four Pillars of Destiny. Your birth moment written as eight characters — a stem and a branch each for the year, month, day and hour. The chart shows the elements you carry in surplus, the ones you lack, and the ten-year cycle you are currently inside.
Ten heavenly stems and twelve earthly branches combine into a sixty-term cycle. Four pairs — one per pillar — give eight characters. Every stem and branch carries one of the five elements, in a yin or yang form.
The stem of the day pillar stands for you. Everything else in the chart is read as its relationship to that one character: what supports it, what it produces, what it controls, and what presses on it.
A chart is not a verdict. It describes a distribution — too much fire, no water, wood without earth to root in. Practice consists of feeding what is missing through timing, direction, occupation and conduct.
Enter a birth date and local birth time. The calculator returns the four pillars, your day master, and the element distribution across all eight characters.
Solar-term boundaries are approximated to fixed calendar dates, so charts for births within a day of a term change should be confirmed by hand. Time is taken as local clock time without longitude correction.